Association between depressive symptoms and all- cause mortality in Chilean adult population: prospective results from the National Health Survey

Purpose: Depression is a prevalent disorder with effects beyond mental health. An association with mortality has been reported, however, evidence is mixed and limited to a few high-income countries. This study aims to assess the association between depressive symptoms and all-cause mortality in the Chilean population. Methods This prospective study used data from the Chilean National Health Survey (ENS). Data from 3,151 and 3,749 participants from the 2003 and 2010 ENS respectively were linked to mortality register data. Cox survival analysis was performed using days from interview as time-to-event. The main exposure was depressive symptoms, measured with CIDI-SF (cut-off ≥ 5), and the outcome was all-cause mortality. The study period was limited to 8.5 years to allow for the same length of follow-up in both cohorts. Results 10% and 8.5% of participants from the 2003 and 2010 cohort died during the follow-up. Adjusting for age and sex, those with depressive symptoms were 1.50 (95% CI 1.11–2.02) and 1.51 (95% CI 1.11–2.04) times more likely to die than those without symptoms in the 2003 and 2010 cohort, respectively. In fully adjusted models, participants with depressive symptoms were 1.38 (95% CI 1.02–1.86) and 1.38 (95% CI 1.02–1.88) times more likely to die compared to those without symptoms in the 2003 and 2010 cohort. Conclusion Addressing mental health in the Chilean population could contribute not only to healthier but longer lives as well. Future research should collect data on more points in time to assess the effect of trajectories of depressive symptoms on mortality.